Die-casting



Aug. 15, 1933. L.. H. MORIN DIE CASTING Filed Feb. s. 1951 N 7Sheets-Sheet 1 ATTORNEY Allg. 15,1933. L, H, Mom-N 1,922,598

' DIE CASTING Filed Feb. 6, 1931 7 Sheets-Sheet 5 INVENTOR ATTORNEY Aug.15, 1933. L. H. MoRlN 1,922,593

DIE CASTING Filed Feb. e, 1951 'r sheeis--sheetV 4 'ATTORNEY L. H. MoRlNf 1,922,598

DIE CASTING Filed Feb. e, 1951 rr sheets-sheet 5 Aug. 15, 1933.

Aug. l15, 1933.

l L. H. MORIN DI: CASTING Filed Feb. 6, 1931 '7 Sheets-Sheet 6 L. H.'MORIN Aug. 15,` 1933.

DIE CASTING Filed Feb. 6, i931 7 Sheets-Sheet '7 mvENToR 04..., wa Mw BYd;

Patented Aug'. 15, 1933 11m-CASTING Louis H. iorin, New York, N. Y.,assignor to Doehler Die-Casting Co., a Corporation' of New YorkApplication February 6, 1931, Serial No. .513,803

11 claims. (ci. 2z-2oo) My invention relates to the art of die-castingin which castings aremade by forcing molten metal, under pressure, intoa mold or die. Al-

though considerable progress has been made in this art, and castings maynow be made which have complicated shapes and with such accuracy thatsubsequent machining operations are rendered unnecessary, the industryhas been restricted to casting articles from certain metals such, l0Vfor example, .as zinc and aluminum base alloys. Because of the greatsaving which can be eiected by die-casting parts of intricate shape,which Y otherwise would require extensive and expensive machiningoperations, it is desirable to produce 15 die-castings from other metalssuch, for instance,

as brass which are'suitable for many purposes for which the alloys nowused in die-castingcannot be used. 'It has been impossible, however,with the known methods and die-casting machines, to die-cast such metalson a commercial basis, and it is a purpose of my invention to renderpractical the commercial production of diecastings from metals otherAthan those in general The vprincipal difliculties arising indie-casting other metals than those in general use in the industry arecaused by the high temperatures at which the metals melt. In die-castingbrass, for

instance, by known methods, the high tempera' so ture of the moltenbrass raises the temperature of various parts of the machine andparticularly the dies to suchan extent that the dies are weakened andthe high shrinkage of brass sets up When these metals are die-cast inaccordance strains within the die which impair its accuracy. In fact,after several castings are made the dies A crack and are useless forfurther casting operations. Since the cost of the dies is'the principalfactor in commercial die-casting, this in itself o makes die-castingswith metals having. a high melting point prohibitive. Another seriousdimculty encountered in the casting of metals of com.

paratively h igh melting point is the fact that it has been practicallyimpossible to produce die-1 castings from such metals which areconsistently free from blowholes or shrinkholes.

My invention is based upon minimizing the heat transferred to themachine and the dies, and the utilization of pressures compatible withthe Y production of castings ofiuniform density. The

method. of my invention includes forcing the metal into the die whilethe metal is in a molten condition but near its transition point. Thatis, the metal is vfluid but the temperature of the metal is such. that alowering of the temperature `diately. Thus, the two factors which governthe' to any extent will cause the metal to change to the solid state.When the metal 'is introduced into the die in this conditio it passesfrom the molten condition into the solid state practicallyinstantaneously and may be, and in accordance with my invention is,ejected from the die immheat transferredfrom the molten metal, namely,the temperature at .which the metal is introduced into the die and thelength of time the hot metal 05 is in contact with the die, areminimized.

The pressure under which the metal is intro` duced into the die -is alsoanV important factor; in die-casting metals having a comparatively highmelting point as this determines the time requiredY to fill the moldcavity ofthe dieand also the density and uniformity of the castingproduced. I have found that in order to produce satisfactorydie-castings from 'metals having a comparatively high meltingl point,which are forced into the die at or near the transition point, the metalmust be introduced into the, die under a much greater pressure than thatused with the ordinary die-casting metals, and in accordance with mymethod, l introduce the metal into the 8 die under a pressure rangingbetween 6000 and 9000 pounds per'square inch. Under this metal pressure,the mold cavity of the die is filled prack tically instantaneously, andthe casting' produced is free fromblowholes or shrinkholes. e

An advantage of my invention is the fact that it is .equally applicableto die-'casting the ordinary metals used in the die-casting industry.

with my invention, the casting produced has a greatendensity than theordinary die-casting; it is free from blowholes or shrinkholes; and itexhibits greater strength and a smoother surface.

My method of die-casting may be convenien ly carried out by a machinewhich I have designed 95 for that purpose. The machine includes a.pres-a sure pot which is adapted to receive a charge of molten metal.The pressure pot is provided with an orice through which molten .metalintroduced into the pot is discharged into the mold cavity of a die, andthe pot is adaptedto have a, die-part rigidly affixed in operativerelation thereto withthe post of the die-part communi-` cating with theorifice through the wall of the w pressure pot. Means are provided forexerting a pressure, on the metal in the pressure-pot to force the metalthrough the orifice, at a high velocity, and -into the die.

. Associated with the pressure pot, there is a u movable die carrier for.moving a die-part in to and out ofoperative relation with va die-partsecured in operative relation to the pressure pot.

Core pulling and ejecting mechanisms are provided which are actuatedupon movement of the die carrier to open the dies, the core pulling andejectinginechanisms pulling the cores and eject.

ing the casting. The automatic operation of the core pulling andejecting mechanisms is an important factor in my invention as it renderspossible immediate ejection of the cast metal which if allowed to remainin the die any length of time freezes fast t the cores, and, of course,the heat transferred to the die from the hot metal is proportional tothe time the metal is in contact with the die.

An advantage'of this machine is the fact that the pressure pot isseparate from the melting pot. This construction renders practical thecasting of pure aluminum as the molten aluminum is not in contact withthe pressure pot a sufhcient length of time to absorb iron from thepressure pot, and the high pressure which the machine is adapted toexert upon themolten metal is sufficient to force pure molten aluminuminto -the die without the addition to the aluminum of some agent such assilicon to increase the fluid' ity of the molten aluminum. Thisadvantage is of great practical importance because pure aluminum doesnot tarnish when exposed to prevailing conditions of service, and it istherefore only necessary to polish the casting which is produced in themachine.

I shall now describe the invention in connection with the machineillustrated in the accompanying drawings which machine constitutes oneembodiment of .my invention and which'is designed for carrying out mymethod. r

In the drawings:

Fig. 1 is a side elevation of a die-casting machine constructed inaccordance withrmy invention;

Fig. 2 is a-n end elevation of the same as viewed from the right in Fig.1 and showing the pressure end of the machine;

- Fig. 3 is a plan of the same partly in section on the irregular line3--3 of Fig. 1; Y

Fig. 4 is a diagrammatic arrangement ill trating the system andapparatus used in obtaining the high pressures usedby the machine;

5 is a longitudinal section of a pressure cylinder;

Fig. v6 is a. transverse section of the same takenon the line 6-6 ofFig. 5

Fig. '1 is a longitudinal section of a manual control valve for thepressure cylinder;

. Fig. 8 is an end elevation of the same;

Fig. 9 is a longitudinal section of .the pressure pot and its associatedmechanism;

Fig. 10 is an enlarged 'fragmentary plan taken on the line 10-10 ofFig.,9 and showing a. cross beam with a cover plate removed;

Fig. 11 is an enlarged fragmentary, SQtional end elevation of the partsshownin Fig. 10;

12 is a fragmentary, sectional end elevation of the cams for operatingthe die carrier;

Fig. 13 is a fragmentary, sectional, side eleva-A Fig. 16 is an enlargedsectional elevation of a clutch mechanism.

'I'he machine shown in the drawings comprises Vsupport a plate 4 whichspans 4the frame members and is secured thereto by means of bolts 5extending through the plate. On this frame, there is mounted a standard6 which is secured to the plate by means of bolts 7 extending through alateral flange 8 formed on therlower end of the standard. 'Ihis standardincludes two solid upstanding side portions 9 and a central portion 10which forms a vertical slot in which a block 11 forming the pressure potproper is received.'

The block forming the pressure pot is formed kin two parts, one of which11a is bored longitudinally thereof to form a pressure chamber which isadapted to receive a charge of molten metal and the other part 11bforming the base of the pressure chamber. The two parts are held inproper relation to each other by an overlapping flange connection asshown in Fig. 9. -A hole is provided through one wall of the pressurepot, and in this hole, there is a bushing 12 which has a discharge oricethat communicates with the pressure chamber of the pressure pot. Thedischarge orifice of the bushing 12 tapers outwardly from the chamber ofthe pressure pot, so that metal solidifying in the orifice will be drawnout of the orifice with the casting. A llateral flange formed on theouter end of the bushing abuts against the outer surface of the pressureblock and serves to hold the bushing in place. The ope'n side of theslot in the standard in which the pressure block is received is closedby a die plate 13 which extends across the slot vand is secured to theside of the standard by bolts which engage T-shaped slots formed in thesurface of the standard. The surface of the die plate abutting againstthe side of the pressure pot is recessed to receive the flange of the.bushing 12.

The opposite face of the die plate is also recessed and carries'adie-part 14 with the post of the diepart communicating with thedischarge orifice of -the pressure pot. The pressure pot is held Thebase of the pressure chamber formed inf the pressure pot tapers to anopening of lesser diameter that extends through the base of the-pressure pot and the standard which forms a receptacle for the pressurepot. This latter opening is aligned with an opening which extendsthrough the plate of the frame. Within th'e pressure p'ot there is apiston 18 the lower end of which is complementary to the taper of thebase of the pressure chamber. A projection 19 on. the lower end of thispiston extends into and is secured in a recess in the end of a rod 20which extends through the aligned openings in the base of the pressurepot, the standard and the plate of the frame. The opposite end of therod is also recessed and receives the end of a rod 21 of lesser diameterwhich is secured to the rod and forms a continuation thereof. Thereduction in diameter of the composite rod formed by the rods 20 and 21forms aledge for apurpose which will hereinafter appear. The lower endof the rod 21 normally rests upon a resilient support which is ofsufficient height so that the piston is held in the pressure pot atapproximately the transverse center of the pressure chamber. and coversthe discharge orice. The circumference of the piston is provided withtwo semicircular grooves which' are .adapted to catch and retain anymolten metal flowing past the piston.

. The resilient support, upon which the end of the composite rodextending from the piston rests,

V includes a bracket having legs 22 which end in lateral anges 23 thatmay be secured to the floori or a base upon which the machine -ismounted, and a cross piece 24 that extends between these legs and isintegral-therewith. The cross piece is provided with two verticalopenings which are adapted to receive bolts 25 which extend upwardlytherefrom. A plate 26 extends between these bolts and has openings toreceive the bolts. Between the plate andthe cross piece of the bracket,there is a compression spring 27 surrounding each of the bolts, and theplate'is prevented from moving oif of the bolts by nuts 28 threaded onthe ends thereof. At the center of the plate, there is provided anabutment 29'upon which the end of the composite rod extending from thepiston in the pressurechamber rests.

The side upright members 9 of the standard 6 forming the frame for thepressure pot are bored.

longitudinally thereofl to receive upstanding supporting rods 30. Theserodshave a reduced end portion which extends through the plate of theframe; and the ends of the rods are threaded to receive nuts 31 whichsecure the rods -to .the frame. The upper ends of these rods are alsoreduced and extend through lugs 32 formed on the sides of a cylinder 33which lugs are bored so that the reduced ends of the rods may passtherethrough, one end of each lug resting upon the ledge'formed byreducing the diameter of the rods and the other end abutting against anut 34 threaded on the end of the rods and securing the cylinder on thereduced end of the rods. The cylinder is formed by boring the block 33longitudinally thereof. The lower end of this bore is closed by a head35 which has a projection 36 extending into the cylinder, vthe inner endof the l projection abuttingagainst a shoulder formed in the cylinderwall. This head is provided with'an opening therethrough for a pistonrod, a bushing 36a being interposed between the sides of the openingthrough the head and the piston rod. The bushing is provided with a angeat its inner end and on this flange there is a circular packing strip 37of U-shape in cross section. The headis secured to the end of thecylinder by bolts38 and' is positioned by the projection 36 extendinginto the cylinder and ani` annular positioning lug 39 which is receivedin `a. complementary groove in the end of the cylinder. The head 40closing the upper end of the cylinder is of dome shape. This 'head islikewise secured to the end of the cylinder by means of bolts 41 andpositioned by n annular positioning lug 42 received in a complementarygroove. The head is'.V also provided with a cylindrical projection 43extending into the bore ofthe cylinder.

there is a transverse passage 50 extendingf through the valve .chest.This passage communicates with thecenter of the valve chamber through aseries of ports 50' and is adapted to supply fluid under pressure to thevalve chamber to be distributed. to the cylinder by a piston ,valve 51having a reduced central portion which is` slidably mounted within thevalve chamber. The piston valve 51 has rods 51a and 51b extending fromthe ends thereof into the hub. shaped heads. On the side of the valvechamberopposite to the cylinder there is an Aexhaust passage 52 whichcommunicates withV the valve chamber throughA branch passages 52a and52h at both ends of the valve chamber.

In the cylinder, a piston is reciprocally mounted. The piston includes asolid central portion 53 which is tted 'on-a reduced portion of a pistonrod 54. This solid portion of the piston has peripheral grooves formedin each end thereof, andtliese grooves form housings for U-shapedpacking strips 55. The grooves formed in` the lower end of the pistonare closed by a plate 56 that abuts against the shoulder formed byreducing the diameter of the piston rod. vThe pis-- ton rod iis furtherreduced in diameter beyond `the solid portion of the piston and on thisreduced portion of the piston rod, there is mounted a collar 57 which isprovided with a lateral flange 58 which forms the upper face or head endof the piston, and with the grooves formed in thel upper end of thesolid portion of the piston constitutes a housing for one of the packingstrips 55. `The collarv has a small piston 59 formed on the upperendthereoi and is secured in place by a nut 60 threaded on the end ofthe piston rod, a washer 61 beinginterposed` between the nut and the endof the collar. The piston formed on the upper end of the collar isadapted to enter the cylinder formed by the cylindrical projectionextending from the dome-shaped head on the upper end of the cylinder.This piston is provided with a groove in which a packing ring 62 isplaced, one side of the, groove being formed by the washer 61 betweenthe collar and the nut. The -piston traps some of the pressure fluidlmedium in the dome shaped head of the cylinder and the trapped fluidacts as acushion to cushion the upward stroke of the piston. The piston;through the piston rod, 'and the cross head 63 is adapted to actuate aplunger 64 which is aligned with the pressure chamber of the pressurepot. Y

The crosshead 63 extends between the cylinder supporting rods which passthrough hub shaped portions formed on the sides of the -cross head, thecross head being slidably mounted on is provided with a recess whichreceives a lateral flange 6 5 formed on the end of the piston rod.Acollar 66 surrounding the piston rod and having an annular flange 67 issecured to the upper surface of the cross head by bolts 68 which extendthrough the flange of the collar and serve l to secure the flange of thepiston rod n the recess formed in the cross head. The plunger 64 issecured to the lower surface of the cross head in the same manner, thatis, a ange 69 is provided on the end of the plunger which ange isreceived in a recess in the lower surface of the cross head. An annularplate 70 surrounding the plunger is secured to the cross head by meansl0f bolts 71 which clamp the flange of the plunger in the recess in thecross head. The plunger, as hereinbefore explained, is aligned with thepressure chamber of the pressure pot. The length o f stroke of thepiston 53 is such that when the piston is in its lowermost position; theplunger extends into the pressure pot and forces the piston in thepressure pot against the bottom of the pressure chamber.

Extending from each of the hubs of the cross head surrounding thecylinder supporting rods, there is a lug 72 which has an openingtherethrough to receive the reduced end portions of rods 73 whichreduced end portions extend through the lugs and are secured therein bynuts 74 threaded on the. end of the rod. These rods pass' throughopenings provided therefor in the plate of the frame and are slidablymounted in these openings. The lower ends of the rods are also reducedinY diameterA and extend through openings in the ends ofv a cross beam75 which spans the rods. The cross beam is held in position on thereduced end of the rods by nuts 76 threaded on the rods.

The cross beam 75 has a slot formed therein at the center thereofthrough which the composite rod extending from the piston in thepressure chamber of the pressure pot passes. The cross beam has anarcuate portion 76a, concentric with the center of the rod passingtherethrough, which has an, annular recess formed therein, a slot beingcut in the side of the annular recess. In this semi-annular recess thereisa hook-shaped cam77 which is adapted to rotate about the central hub78 formed by cutting the annular recess. The cam is provided withdiametrically opposed radial extensions 79, and a lug 80 that extendsinto the slot formed in the side of the annular recess. One end of thecam extends beyond the'cross beam and is secured to a handle 81 by meansof rivets 82. The cam is held in the position shown in Fig. l0 by aspring 83 that is secured at one end to the handle and at the other endto a pin 84 extending from the cross beam. Above the cam, slidablymounted in rectangular recesses, there are two opposed plates 85 whichextend over the cam. These plates are urged towards each other bysprings 86 which surround pins 87 extending into holes formed in theplates. Each ofthe plates has a pin 89 extending therethrough into theannular recess below the plates. These pins form shafts for camfollowers 90 which cooperate with the cam in the annular recess. In theposition shown in Fig. 10, the radial extensions of the cam are to oneside of the cam followers and the plates engage the rod 21 extendingfrom the piston in the pressure pot. As the handle is moved to the left,the radial extensions of the cams engage the cam followers secured toAthe plates and move the plates so as to release the rod. Movement ofthe cam is limited by the lug 80 extending into the slot in the side ofthe annular recess.

plate 91 that is secured to the beam by machine screws.

AAs the piston 53 in the cylinder 33 is forced The plates 85 and the cam77- are held in the recesses in the beam by a cover' downwardly to causethe plunger to enter the pressure chamber of the pressure pot, the crosshead also moves downwardly and through the rods 73 moves the cross beam75. As the cross beam passes the shoulder formed on the composite rod bythe reduction in diameter from the rod 20 to the rod 21 the plates 85,under the action of the springs 86, engage the reduced portion of therod, and as the cross beam is lifted by the upward movement of the crosshead, the plates 85 engage the end of the rod 20 secured to the pistonin the pressure chamber' of the pressure pot and the piston is movedupwardly to the position shown in Fig. 1. It will be apparent that if a,charge of molten metal is introduced into the pressure chamber when thepiston is in its normal position it willbe prelvented from entering thedischarge orifice as this is covered by the piston. As the plunger movesdownwardly, it will force the piston to the base of the pressure chamberand the molten metal will be s'queezed'between the plunger and thepiston and will be forced through the discharge orifice. lower positionthe cross beam extending between the rods which are secured to the crosshead is below the shoulder formed by reducing the diameter of the rodextending from the vpistonin the pressure chamber and the plates abutagainst the reduced portion of the rod. When the piston in the pressurechamber is moved upwardly by the cross beam, the metal remaining in thepressure chamber will becarried upwardly on the piston, the metal in thepressure pot being separated from the metal in the Adischarge orifice bythe action of the piston i'n the pressure chamber. When the piston inthe pressure chamber reaches' the vposition shown in Fig. l the metalmay be brushed from the top of the piston and returned to the meltingpot.

In casting metals having a higher melting point than those commonly usedin the diecasting industry, it is necessary to use much higher pressuresthan are now commonly employed. In fact, for a metal such, for example,as brass, a pressure of from 6000 to 9000 pounds is required. It isimpossible, therefore, jor all practical purposes, to luse a pressuremedium such as compressed air as the apparatus required and the energyexpended in compressing air to a suitable pressure is so expensive thatthe use of ,compressed air as an energy transfer medium is prohibitive.AI have, therefore, devised a system by means of which I may obtain highhydraulic pressure and at the same time obtain that -rapidity ofmovement that is characteristic of an expansible fluid. I obtain therapidity of movement. of a hydraulic pressure medium by building up apressure on the medium against a cushion of air so that the rapidexpansion of air, when the medium is released, is transmitted throughthe inexpansible uid. In the system shown in the drawings, I utilize atank 9 2 for storing a supply of oil and acting as a reservoir for thesystem. The reservoir is provided with a visible level indicator 93 andthe base of the reservoir has a coupling 94 for a pipe connection which.is connected in the system shown through a valve 95 to a supply pipe96. A This supply pipe is connected by a T-fitting 97 to two pipes 98and 99, one side of the T-fitting being connected through a valve 100 tothe pipe 98 which is connected to a supply of oil from which the oil inthe system is'replenished. The other side of the When thev plunger is inthe d of the tank 92 so that the oil from the cylinder isA Thus, in thesystem' reached the motor is stopped.

T-tting is connected `to the pipe line 99 in which there is interposed acheck valve 101. The pipe line 99 supplies oil to the low pressure sideof Da pump 102 to which it is connected through a T'tting 103. The pumpis driven by a motor 104 to which it is directly connected. The highpressureA side of the pump is connected to a T=tting 105, oneside ofwhich is connected to a safety valve 106. A pipe 107 extending betweenthe T-tting 103 and the safety valve 106 forms a bypass around the pumpwhen the pressure exceeds that for which the valve is set. The side ofthe` T-tting at the high pressure side of the pump opposite to thesafety valve is connected to a pipe 108 which is connected through a-cross-tting 109 to one end of the passage 50 through the valve chest ofthe cylinder. The other end of the passage 50 is connected through apipeline 110 to a pressure tank 111, a valve 112 being interposed in thepipe line. which is a cast iron tank, is connected through a pipe 113 inwhich a valve-114 is interposed to a supply of compressed air under apressure of approximately 200 to 300 lbs. per square inch.

Compressed air at this pressure is admitted into` the pressure tank andthevalve 114 in the air supply valve is closed.

' The exhaust passage 52 of the valve chamber is'connected through apipe 115 to the upper end returned vto -the reservoir. shown, oil istaken from the reservoir by the pump and delivered under pressure to thepressure tank which, as explainedabove, has an air cushion formedtherein by admitting air into the tank under apressure of 200 or 300lbs. per square inch. 4The pump is such that it will de. velop apressure of approximately 2500 lbs. per square inch which is impressedupon the oil in the system. The areaof the plunger 64 is pro` portionedwith respect to 'the area of the piston 53 so that a pressure of 2500lbs.-per square inch in the cylinder produces a pressure on the metal inthe :pressure pot exceeding 6000 lbs. per

A pressure gauge 116'is connected to the crosstting 109 through whichthe pump is connected to the valve chest, by a pipe 117. A T-tting 118is interposed in this pipe and a tap is taken from the pipe to apressure regulator 119 through a pipe 120. The pressure regulatorcontrols the 4operation. of the motor to which the pump is directlyconnected. In this way, the pressure in the system is maintainedautomatically for as the pressure goes down the motor is started up andthe pump builds up the pressurev to the normal pressure used. When thispressure is The valve 51 in the 'valvechamber controls the distributionof the oil to the cylinder through the ports 50' and the passages 48'and 49. The valve is actuatedr by the pressurev iluid through the rods51a'and 51h. These rods act in the capacity of pistons to shift thevalvewhen prescasing. The valve has an extension 124 extend` ing throughthe bushing on the end of which The opposite end of this pressure tank,v

extension a handle 125 is secured for rotating the valve. Extendingthrough the handlethere is a rod 126 which is connected at its lower endto a plunger 127 which has a laterally extending flange 128 that extendsunder an arcuate member 80.

129 secured to the valve casing by means of bolts 130 extending througha radial ange 131 formed on the arcuate member. The flange 128 of theplunger is adapted to abut against lugs 132 formed on the inner surfaceof the arcuate 85 member to position the valve, and may be released bypressing a button 133 on the upper end .of the rod to which theplunger-is secured, a

'into which the ends of nipples are threaded.

As shown in Fig. 8, the valve is provided with two passages 136 and 137each of which is adapted to connect two of the radial passages in the100 valve casing together. One of these passages Ib in the valve casingis connected through a pipe 138'to the -lower hub shaped head of thevalve chamber, andA another 13511 is connected through a pipe 139 to theupper hub shaped head 105 of the valve chamber, suitable ttings 139being provided for connecting the pipes 138 and 139 to the hub shapedheads.l One of the remaining passages 135e in the valve chamberisconnected through a pipe 140 to the cros's't- 110- ting 109 throughwhich the pumpis connected to the transverse passage in the valve chest,and the other '135a is connected tothe exhaust passage in the valvechest through a pipe 141.

' Fluid underpressure is supplied through the 11'5 4pipe 140 to thevalve, and when the valve is positioned as shown in Fig. 8, this fluidis transmitted through the passage 137 in the valve to the pipe 139connected to the upper head of the valve chamber, and the pipe 138connecting the 120 lower head of the valve 'chamber' is connectedthrough the passage 136 of the valve to the`pipe 141 leading to theexhaust' passage. The valve therefore is moved downwardly in the. valvechamber to the position shpwn in Fig. 5 in which 125 position thereduced central portion of the valve spans the passages 50 and 49thereby admitting uid under pressure to the lower end o'f the `cyl-1indr which forces the'pi'ston upward. 'I'he end of the valve uncoversthe passages 48 and 52a 1.30l

so that the upper part of the cylinder is connected to the exhaustpassage 52. lDue to the expansion of the air in the pressure tank, thepiston is moved upwardly in the cylinder at the rate of approximatelyninety feet per second. As 135 the valve 122 is moved to the oppositeposition, the upper head of the vvalve lchamber is connected through thevalve 122 to the source of supply and the lowerl head is connected tothe exhaust passage 52 as will be readily apparent. The pis- 140 tonvalve is then shifted to the position opposite to that shown in Fig. 5in which position the reduced portion of the valve spans the passages 48and 50 and opens .the passage 49 connecting the 1ower end of the minderto the exhaust pas- 145 sage 52 through the passage 52h. The piston istherefore moved downwardly Ain the cylinder.

The power, or operating, end of the machine is carried by a frame whichincludes a pair of parallel side frame members 142 and a trans-:

' verse end frame member 143. The side frame members are rigidly securedtogether in spaced relation by a series of tie-rods 144, and the frameis rigidly secured in place with respect to the pressure end of themachine by four parallel frame rods 145 which are arranged in twoparallel planes. These frame rods are rmly secured in the standard 6which holds the pressure pot 11 and extend perpendicularly from thestandard and through the side frame members. The two upper frame rodsextend through hub shaped projections 146 formed on the sides of theframe members and are slidable therein; the two lower rods extendthrough the frame members which have hub shaped portions 147 at each endfor the rods which are slidably mounted in these hub shaped portions.The frame rods are threaded throughout the portions thereof which extendthrough the frame members and are rigidly secured to the frame membersby nuts 148 abutting against the ends of the hubs in which the framerods are received. The frame rods are slidably mounted in the framemembers so that respect to the pressure end to accommodate differentsized dies.

` ed to provide for any tilting of the frame duringY The frame of thepower or die carrying end of the machine is supported through brackets149 that extend downwardly from and forwardly of theside frame membersto which they are rigidly secured. A shaft 150 extends between thebrackets, and through openings provided'thereforin the brackets.Adjacent each bracket, there is rotatably mounted on the shaft 150 aflanged wheel 151 whichrests upon a track 152 supported by a base 153.vBy loosening the nuts 148 at both ends of the hub portions of the framemem--` bers throughwhich the frame rods extend, the frame member may beadjusted with respect to the pressure end of the machine by moving theframe along the tracks. For this purpose, an adjusting screw 154 extendsthrough the shaft 150 in. threaded engagement therewith. The Yad-rjusting screw is rotatably mounted in an arm 155 pivotally mountedbetween the arms of a bracket 156. On the end of the adjusting screwextending through the arm 155, there is mounted a spur gear 157 whichmeshes with a pinion 158 mounted upon andsecured to a short shaft 159extending through and rotatably mounted in the arm 155 on the oppositeside ofthe pivot to that through which the adjusting screw extends. OnYthe end of the shaft 159, there is a hand wheel 160 by means of whichthe screw shaft may be rotated to move the frame. The arm 155 ispivotally mountthe adjusting thereof.

The frame rodscarry a movable die plate 161 I which is slidably mountedthereon, the die plate being provided with hub shaped portions 162through which the frame rods extend. Guide rods 163 are also providedfor the die plate which anism. This toggle mechanism consists of twopairs of links, one pair at the top of the machine and the other at thebottom. Each pair of links includes 3a link` connected at one endl tothe frame of the machine anda link pivotally connected at one end to thedie plate, the opposite ends of the two links being pivotally connectedtogether. The link connected to the die plate has two parallel arms 164theends of which extend between brackets 165 formed on the die plate andYare pivotally secured thereto by a pivot pin 166.

pivotally secured to the link secured to the die plate adjacent the armsthereof by a pivot pin 170. The arms of the bifurcated end of thelinkare strengthened by an integral cross piece 171. Between the arms of thebifurcated end of the link connected to the frame member, another link172 is mounted on the pin 170 connecting the two links together. At theend opposite to that mounted on thepin, this latter link is alsobifurcated. Each arm 172e and 172D of the bifurcated portion of the link172 is secured to a member 173 that is slidably mounted on one of theguide rods of the die plate, the two members 173 being connectedtogether and constituting a cross head.

II'he cross head for actuating the toggle mech` anism of the die plateis operated byA cams 174 formed in the sides of a pair of gears 175, thecross head being operated by these cams through a system of links andlevers. The gears are mounted on a shaft 176 extending between the twoside frame members and through one end thereof, the shaft beingrotatably mounted in the frame members. The contour of the cams formedby recessing the opposed faces of the gears, as shown in Fig. 13, issuch as to reciprocate a link 177 which is mountedv between the gearsand provided with a slot 178 through which the shaft 176 extends. Thelink 177 has cam followers 179 mounted on both sides thereof whichextend into the cam recesses of the gears. The upper end of this link ispivotally mounted between the arms of a lever 180, a pivot pin 181extending through the arms of the lever and the upper end of the link.The lever is pivotally mounted on a bracket 182 which is secured to theinner surface of the transverse end frame member by a bolt 183 whichextends through the frame member. The end of the link 177 is pivoted tothe lever 180 between the ends of the lever.l The upper end of the leveris pivotally secured to one end of a link 184`which extends between theAarms of the lever and is secured thereto 'by a pivot pin 185. Theopposite end of the link 184 is pivotally mounted on a pin 186 extendingbetween the two members 173 slidably mounted on the die plate guide rodsand constituting the cross head.

The gears 175 areoperated from a drive shaft 187 through a train ofreducing gears. The drive shaft is journalled in the side frame membersand a bracket 188 extending from and secured toone of the frame members.Between the bracket and the side frame member, a drive pulley 189 isrotatably mounted on the drive shaft. Also mounted on the drive shaft isa pinion 190 which meshes with a gear 191'mounted upon the shaft 192.This latter shaft, carries a pair of pinions 193 one on either side ofthe gear 191 which mesh with the gears 175. An ordinary brake mechanism187 cooperates with the 'shaft 187 and serves'to take up back lash inthe gears.

The drive pulley has a cylindrical ange 194 extending from the spokes ofthe pulley which ange forms a part of a clutch mechanism for securingthe drive pulley to the drive shaft. Adjacent ,the pulley, there is ahub 195 secured to the shaft, to rotate therewith, by a key 195. Thishub is provided with a-radial flange 197 which, at four equally spacedpoints, has slots formed therefthrough. 1 On each side of the radialange, there is a bracket 198 and 199, which has a projectionv extendingparallel to the axis of the cylindrical flange extending from thepulley. The projection of the bracket 198 extends along the outside ofthe ange and the projection of the bracket 199 y extends along theinside of the flange." Each of these bracketsY carries a friction block200 which is adapted to engage the flange extending from the pulley. Thebrackets are moved with respect to the flange of the hub and in oppositedirections by a lever 201 that is pivotally mounted in the slot formedin the flange. One end of the lever engages-one bracket and the otherend of the lever engages the other bracket. This lever is connected by alink 202 to one end of a rod 203. The opposite end of the rod isconnected to one end of a lever 204 that is fulcrumed between its endsona pivot pin 205 secured on a bracket 206 formed on the hub. The oppositeend of this. latter lever is secured through a link 207 toa collar 208that `is slidably mounted on the shaft. This system oflinks^and.levers'is duplicated at each of four slots in theradial ange197. When the collar 208, which is shown in ltheoperative position inFig. '16, is moved away from the hub the system of links'and levers,above `described will be actuated to cause the'y two brackets to movein Vopposite directions, away from each other, and

release the flange extending from the pulley. Likewise, when the collaris moved to the position y shown, the brackets will be moved' so thatthe flange extending from the pulley.y is firmly clamped between thefriction blocks.

The collar is s hifted along the shaft by a bifurcated bracket 209 thearms of which have projections 210 extending into a circular grooveformed on the collar. This bracketisf'secured to a shaft 211 that isjournalled in huby shaped projections 212=formed integral with the sideframe member.

'. The shaft also carries a bracket 213 having a laterally extending arm214 through which a pin 215 extends that is secured to the frame member.On this pin, a compression spring 216 acts -between a nut on the end ofthe pin and the' arm'extending from the bracket, the spring urging .thearm in a'direction to move the shaftso as to disengage the clutch. Onvthe end of the shaft, there is a handle 217 by means of vwhich theclutch may be' manually operated. The bracket 213 carrying the lateralarm is also provided with an arm 218 that carries a cam follower inoperative relation to a cam 219 secured on the end of the shaft 176which cam-is adapted to hold the clutch in the operative positionagainst the action of the spring when the .clutch has beenA movedthereto by the handle. vThe cam is such, having one V-shaped groove,that when the clutch is actuated to cause the machine to be operated itis held in the operativeposition while the shaft 176 makes onerevolution, until the cam follower again reaches the groovein the camwhen the clutch is released. Adjacent the end of the shaft 211, there ismounted a bevel gear 220. This gear meshes with a companion gear 221mounted upon a short horiz'ontal shaft 222 which carries a spur gear 223that meshes with a gear 224 secured on the' end of a shaft 225 which isjournalled at one end inv av bracket 226 housing the gears 223 and 224.The other end of the shaft 225'extends through a bracket 227 secured onthe plate 4 of the frame of the pressure end of the machine, and has'ahandle 228 secured on the 'end thereof by means of which handle theclutch-may be operated from the pressure end of the machine as will bereadily apparent. r

The power end ofthe machineis also provided with automatic core pullingand ejecting mechanism. The automatic pulling of cores and ejecting thecasting fromthe die is a very importantI @factor in the casting of'metals having a high mediately after the metal is introduced into thedies the. metal will freeze fast to the cores. To eliminate thisdifficulty, 1p1-Ovide an automatic core pulling and ejecting mechanismwhich ,is actuated by movement of the movable die plate 161. To the dieplate there is secured an ejector box 229the sides of which are open.The ejector box carries a die-part 230 which is-adapted tocooperate'with the die-part 14 in the die plate 13. The mold cavities ofthe die-parts are cut so that when the die-partstar separated-.the castmetal remains in the mold cavity of the die part 230. The dieillustrated has three core pins, two lateral core .pins 231 and 232 andone longitudinal core lpin 233. The ends of the lateral core pins aresecured to lateral racks 234 and 235 respecl tively by lugs 236. Theracks engage pinions 237 which are mounted in the ejector box. Alsoengagling these pinions there are longitudinal racks 119 -234a and. 235awhich extend intothe open porwhich communicates with a recess in itsinner surface. The ,end of the rack 235a extends through the opening inthe plate and has a flange 239 on the end thereof which is received.

in the recess communicating with the opening. the flange being= firmlysecured between the two plates. The other longitudinal rack 234a ex'tends through the core plate' and has a nut 240 4'on the end'thereofwhich is of greater diameter than the opening in the core plate throughwhich the .rack extends. The longitudinal core also 35 extends throughthe core plate and has a nut 241 on the end thereof. It will be seen,therefore, that as -the core plate moves relative to the die plate, in adirection away from the dieplate,

it will move the longitudinal racks, either by virtue of the fact thatthe rack is secured therein lor by engaging the nut on the end of therack.

.The racks will rotate the pinions 237. which will move the lateralracks and the core pins which vare secured thereto. The longitudinalcore pin .the longitudinal core pin 233 are moved in the oppositedirection by the engagement of the core plate with collars 242 securedon the rack and core pin. It will be apparent that the distance the corepins are moved depends upon their engagement with the core plate.

The ends of the core plate extend through openings in the sides of theejector box. To each of the extended ends of the core plate an operatingrod 243 is secured and extends perpendicularly to the core plate alongthe side of the machine, the rods being supported by projections 244formed on the sides of the die plate through which they extend. The rodsalso extend through openings in projections 245 formed on the members173 constituting the cross head of the toggle mechanism. The rods areslidably mounted in the openings in these projections arid arethreadedthroughout the distance that extends throughthe projections.2461) threaded on the rods on either side of the projections on thecross head are adapted to be engaged by the projections and by theengagement of the projections and the nuts to move the rods and the coreplate with the cross head which moves relative to the die plate. Thus,as the cross head moves in one direction the projections will engage oneof the nuts and draw the core plate in the direction of movement of thecross head. As the cross head moves inthe opposite direction, forinstance, to move the die plate to close the dies, the projection on thecross head will engage the nuts 246a on the rods to move the core plateto insert the cores in the die.

Within the ejector box, there is also an ejector plate 247. This plate,like the core plate, is composed of two plates secured together andcarries a plurality of ejector pins 248. The ejector pins have conicallyshaped heads which are received in a recess in the inner surface of oneof the plates and the pins extend through openings in the plate and thedie. When the dies are closed, as shown in Fig. 15, the ends of theejector pins are flush with the Wall of the mold cavity of the die. Theejector plate also extends beyond the sides of the ejector box and has apair of lugs 249 formed thereon on each side thereof. Through each ofthe lugs formed on the ends of the ejector plate 'an operating rod 250extends and is secured to the plate. The rods extend perpendicularlyfrom the plate and parallel to the rods 245 and in the same verticalplane. The ejector plate operating rods extend through plates 251secured to projections 252 formed on the sides of the frame of themachine and have nuts 253:1 and 2531) threaded thereon on either side ofthe plate 251. As the die plate moves to open the dies, to the positionshown in Fig. 1, the ejector plate moves with the die plate until thenuts 253a on the rods abut against the plates 251 when further movementof the ejector plate is restrained. The die plate, however, continues tomove relative to the ejector plate and the ejector pins extend into themold cavity of the die and force the casting out of he mold cavity. Asthe die plate is returned to the position in which the dies are closed,as shown in Fig. 15, the ejector plate moves with the die plateuntill-the nuts 253b on the ends of the rods engage the `plate and holdthe ejector plate from further movement with thedie plate so that thecontinued movement of the die plate withdraws the core pins from themold cavity.

'Ihe operation of the machine is as follows: When the machine is aboutto be operated, the dies are closed, in the position shown in Fig. 15,and the plunger 64 is withdrawn from the pressure pot as shown by Figs.1 and 2, the piston in Y the pressure chamber being at the transverseNuts 2 46a and' center thereof. `The operator ladles metal from themelting-pot (not shown) which is separated from the machine andintroduces the metal into the pressure chamber of the pressure pot. Hethen actuates the valve controlling the plunger and the plunger iscaused to descend at a speed exceeding'60 feet per second, ashereinbefore explained. As the plunger moves downwardly, yit forces thepiston in the pressure pot to the bottom of the pressure pot, therebyopening the discharge orifice. The metal in the pressure pot is squeezedbetween the plunger and the piston under a pressure of from 6000 to 9000pounds per square inch and is forced through the discharge orifice. Theoperator then draws the valve to the opposite position to raise theplunger and at the same time operates the handle 228 to start the powerend of the machine. As the clutch engages, and the shaft 176 is rotatedthrough the 'train of gears hereinbefore described the cam 219 engagesthe cam follower on the shaft 211 and holds the clutch in the operativeposition. Rotation of the gears 175 causes, through the cam and camfollowers, the link 177 to operate the lever 180, moving the leverupwardly. The lever operates to draw the link 184 and the cross head ina direction away' from the pressure end of the machine. Movement of thecross head breaks the toggle and causes the die plate to move along theframe rods to the position shown in Figs. 1 and 3. The core pulling andejecting mechanism are actuated upon movement of the die plate ashereinbefore explained and the casting is ejected from the die. As thegears continue to rotate, the l'mk 177 is moved downwardly and the leveris actuated to move the cross head towards the pressure end of themachine. The die plate is thus nroved to close the dies and is lockedinthe closed position by the toggle mechanism. The machine is then inposition to repeat the cycle just described.

It is obvious that various changes may be made by those skilled in theart in the steps of my method above described for carrying out thatmethod within the principle and scope of my invention as expressed inthe appended claims.

I claim:

1. The method of casting metal which includes introducing the metal in amolten condition into the mold cavity of a die under a pressureexceeding 6000 pounds per square inch, and ejecting the metal from thedie immediately after the mold cavity of the die is filled.

2. The method of casting metals which includes introducing the metal ina molten condition into the mold cavity of a die under a pressureexceeding 6000 pounds per square inch, maintaining the pressure on themetal until the mold cavity is lled and immediately thereafter ejectingthe metalpfrom the die.

3. The method of casting metals which includes introducing the metal ina molten condition and near its transition point into the mold cavity ofa die under a pressure exceeding 6000 pounds per square inch,maintaining the pressure on the molten metal untilthe mold cavity of thedie is filled, and immediately thereafter ejecting the metal from thedie.

4. The method of casting metals having a high melting point, whichincludes introducing the metal in a molten condition and near` its tran#sition point into a pot having a discharge nozzle registering with themold cavity of a die, confining the molten metal in the pot, exerting apressure exceeding 6000 pounds per square inch' on the metal in the pot,permitting the metal to sol now through the discharge nozzle into themold cavity of the die under the action of the pressure exerted on themetal, and' ejecting the metal from the die immediately after the moldcavity of the die is lled.

5. The method of casting metal having a high melting point whichincludes introducing the metal in a molten condition and near itstransition point into a pot having a discharge nozzle registering withthe mold cavity of .a die, the nozzie being closed when the metal isintroduced into the pot, confining the metal in the pot, exerting apressure exceeding 6000 pounds per square inch on the metal in thepotand simultaneously opening the discharge nozzle of the pot to permitthe metal to :flow into the mold cavity ofthe die, and ejecting thecasting from the die.

6. The method of casting metal having a high melting point such as brasswhich includes introducing the metal in a molten condition and near itstransitionpoint into a pot having a, discharge nozzle lregistering withthe mold cavity of a' die,

Athe nozzle being closed when the molten metal is introduced into thepot, confining the metal in the pot, exerting a pressure exceeding 6000pounds per square inch on the metal and simultaneously .opening thedischarge nozzle, maintaining the pressure on the metal until the moldcavity of the die is filled with the metal, separating the metalremaining in the pot from the metal entering the die, and ejecting thecasting from the die.

f1. The method of die casting substances having a high melting point andviscous when molten which comprises confining the substance in a moltencondition within a pressure chamber having a passage communicating withthe mold cavity of a closed die,` exerting a pressure on the moltensubstance exceeding 6000 pounds per square inch to force the substanceat a high velocity into the mold cavity of the die, and ejecting thesubstance from the die immediately after the mold cavity of the die isiilled.

8. The method of die casting a substance having a high melting' pointand viscous when molten which comprises conning the substance in amolten condition Within a pressure chamber having a passagecommunicating with the mold cavity o a closed die, exerting a pressureon the molten substance in the form of an impact and exceeding 6000pounds per square inch to force the substance at a high velocity intothe mold cavity of the die, and ejecting the substance from the dieimmediately after the mold cavity of the die is illed.

9. The method of casting metal having a high melting point whichincludes confining the metal in a molten condition Within a pressurechamber having a passage communicating with the mold Acavity of a closeddie, exerting a pressure on the molten metal in the form of an impactand exceeding 6000 pounds per square inch to force the metal at a highvelocity into the mold cavity of the die, and ejecting the metal :fromthe mold cavity of the die immediately after the mold cavity of the dieis lled.

10. The method of casting metal having a high melting point whichincludes confining the metal in a. molten condition and nearits'transition point Within a pressure chamber having a passagecommunicating-with the mold cavity of a closed die, exerting a pressureon the molten metal in the form of an impact and exceeding 6000 poundsper square inch to force the metal at a high velocity into the moldcavity of the die, and ejecting the metal from the mold cavity of thedie immediately after the mold cavity of the die is lled.

11. The method of casting metal having a high meltingv point whichincludes introducing the metal in a molten condition and near itstransition point into an open pressure chamber having a dischargepassage 4communicating with the mold cavity of a closed die, thedischarge passage being closed when the molten metal is introduced intothe pressure chamber, confining the Y metal in the pressure chamber,exerting a pressure on the metal in the form of an impact and follow uppressure, the pressure on the metalV

